Daily Archives: December 16, 2014

Short Primer on Effective Energy Upgrades For You Part 3: Improve HVAC Operation

Here is another smart, effective energy upgrade that will not only save you significant energy costs (if done right), but will also result in other benefits. One of the biggest users of energy is your heating, ventilation and air conditioning (HVAC) systems. A lot of building managers buy boilers, rooftop units, etc., install them, and then leave them alone or just have an outside contractor look at them occasionally. Perhaps people think they work automatically. But HVAC operation should be taken seriously – to minimize energy costs and to reliably provide proper temperature control for your workers to be efficient or your customers to be comfortable and buy.

The first item to consider is the design and efficiency of the system. Since HVAC systems often last a decade or more, when buying a new or replacement system, it is important to consider the right size (for the area treated) and its rated efficiency. Saving a few bucks now to buy a relatively inefficient system will cost your company a lot in the future. Efficiency is indicated by the energy efficiency rating (EER) or SEER. Many units now are available with an EER of 14 or higher. If you are currently using one with an EER under 9, it may be cost-effective to replace it now with a more efficient one, even if it has not reached its end of life. The difference in electricity costs may justify it.

Just as important is to ensure you operate your HVAC units optimally. All HVAC units contain filters to filter dust and other items from the outside air that is drawn in. While one may simply follow manufacturer’s recommendations on how often to replace the filters, it is important to not blindly follow the recommendation, but instead, physically go onto the roof and look at your units in action, and check the filters themselves. Every situation is different. I worked with a facility which followed the manufacturer’s direction of replacing filters once every 6 months. However, the filters from the biggest units (drawing in more outside air) were filthy with caked-on dust well before 6 months. Was the manufacturer wrong? Not necessarily. The building was located across from a facility that stores different rocks, sand, and other materials. It is probable that dust from this facility brought in by the wind caused the filters to cake up sooner than normal. A dirty, caked filter has two effects on an HVAC unit. It causes the fan to work harder to bring in more air to meet system requirements. One study showed that a dirty filter results in an increase in a unit’s electricity usage by about 9%. Plus, dust that penetrates the filter can damage the interior parts of the unit (condenser coils, etc.), reducing its life and efficiency. More filters and the labor to change them are fairly cheap and worth it to avoid these issues.

One more thing to consider periodically is whether the conditioned air is reaching the zone it is supposed to service. Sometimes internal duct work is partially obstructed, shunting warm or cool air out certain vents and not others. Building management should occasionally monitor whether changes of this nature occur periodically. Again, you want to get the most out of the equipment you paid a lot for. If conditioned air is not distributed properly, a simple inspection of the ductwork could find and allow correction of the problem.

CCES has the experts to help you assess your boilers, air conditioning, and related systems, and advise you on planning new systems and how to better maintain your current ones. We can help you get the best use of your system, to get your money’s worth, and make your workers and customers comfortable. Contact us at karell@CCESworld.com or at 914-584-6720.